&lpar;1&rpar;Strict control of the content of harmful ingredients such as S&comma; P&comma; H&comma; O&comma; N&period; Non-Destructive Testing for the parts to ensure that their internal qualitycomply with standard&period;&lpar;2&rpar;The mechanical properties of metal are in accordance with API 16A standard&comma; HRC≤22&comma; the chemical composition in accordance with API Spec 16A&lpar;GB&sol;T20174-2006&rpar;&comma; All metals in contact with wellbore fluids per NACE Spec MR-0175-2003 for H2S&period;&lpar;3&rpar;The temperature level of the metal material is T-20&comma; the temperature level of the non-metal material is BB&period;l The top sealing surface of Ram BOP is treated with preservatives&period; Stainless steel welding and the corrosion-resistant alloy plating are adopted&period;&lpar;4&rpar;The Surface of ram shaft is chrome plated&period;&lpar;5&rpar;The connection of Ram BOP with oil tube is NPT 1'' box end&comma; C&sol;Woil tubing support withNPT 1'' box end&period; The connection of Annular BOP with oil tube is Rc1-1&sol;2'' box end&comma; C&sol;W oil tubing support with R1-1&sol;2''×NPT 1'' box end&period;&lpar;6&rpar;The flange bolts and nuts are in accordance with GB&sol;T 22513-2008&comma; closed type bolt complies with GB&sol;T 20174-2006&comma; all connection threads are metric thread&period;